News/Press releases

Wild chimpanzees eat tortoises after cracking them open against tree trunks

An international team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig and the University of Osnabrück, Germany, have observed wild chimpanzees in the Loango National Park, Gabon, eating tortoises. They describe the first observations of this potentially cultural behavior where chimpanzees hit tortoises against tree trunks until the tortoises’ shells break open and then feed on the meat.

Mothers’ presence influences the reproductive success of their adult sons

In many social animal species individuals share child-rearing duties, but new research from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, finds that bonobo mothers go the extra step and actually take action to ensure their sons will become fathers. This way bonobo mothers increase their sons’ chance of fatherhood three-fold.

So far Denisovans were only known from a small collection of fossil fragments from Denisova Cave in Siberia. A research team led by Fahu Chen from the Institute of Tibetan Plateau Research, CAS, Dongju Zhang from Lanzhou University and Jean-Jacques Hublin from the Max Planck Institute for Evolutionary Anthropology now describes a 160,000-year-old hominin mandible from Xiahe in China. Using ancient protein analysis the researchers found that the mandible’s owner belonged to a population that was closely related to the Denisovans from Siberia. This population occupied the Tibetan Plateau in the Middle Pleistocene and was adapted to this low-oxygen environment long before Homo sapiens arrived in the region.

By focusing on a group of organisms taxon-specific databases make a broad range of high-quality data accessible

We used data from the IUCN SSC A.P.E.S. database, to show the wealth of information that can be derived from a database that focuses on a specific group of organisms. For this study we focused on the western chimpanzee, a critically endangered subspecies of chimpanzees. Many taxon-specific databases already exist, but are largely underfunded. These databases are, however, in a unique position to fill the niche between local data collectors and global data bases to contribute to closing the large gaps in biodiversity data that still persist. More and more data on patterns and trends of biodiversity are becoming available. However, even though a lot of data have been and are being collected, they are often not accessible to researchers, decision-makers, planners and conservation practitioners.

DNA sequences from Indonesia and New Guinea reveal new branches of the Denisovan family tree

As they dispersed out of Africa anatomically modern humans interbred with their close relatives, the Neanderthals and Denisovans. An international research team examined DNA fragments passed down from these ancient hominins to modern people living in Island Southeast Asia and New Guinea. Their study suggests that the ancestry of Papuans includes not just one but two distinct Denisovan lineages, which had been separated from each other for hundreds of thousands of years. In fact, one of those Denisovan lineages is so different from the other that they might even be considered an entirely new group of archaic hominins.

Songbirds that work together with raising their young coordinate its attention and exchange itself intensively with each other

Cooperative breeding may facilitate the development of sophisticated communicative abilities such as intentionality and joint attention skills. Two new studies of researchers of the Max Planck Institute for Ornithology in Seewiesen, the Max Planck Institute for Evolutionary Anthropology in Leipzig and the University of Osnabrück provide the first evidence that a cooperatively breeding bird species (Arabian babblers) demonstrates distinct hallmarks of joint-attentional skills, which have been traditionally ascribed to humans only. This result also shows that an ape-like cognitive system is not a necessary pre-condition for joint-attention skills.

Male chimpanzees reduce aggression when social relationships in their group are unstable

An international team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, conducted behavioral observations and collected urine samples for cortisol analysis of male chimpanzees of the Taï National Park, Ivory Coast, during periods of intense male-male competition. They showed that all males had higher stress levels during periods of increased male-male competition while aggression rates were actually lower during this time. This may indicate that in times of social instability animals refrain from aggressive actions to avoid escalation of conflicts and to promote group cohesion.

Psychologist Daniel Haun is joining the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) as new Director on 1 April 2019. He was most recently a Professor for Early Child Development and Culture at Leipzig University and the Director of the Leipzig Research Center for Early Child Development. Haun is interested in the ways in which human cognition adapts to, shapes and enables cultural diversity.

Visual artists Elmar Hermann and Emanuel Mathias are interested in the relationship between science and art, language and image. In their new exhibition they address simple principles of visual communication.

Yawning is contagious in both chimpanzees and humans, a possible proof that both are empathic being. Yawning is a reflexive-instinctive behavior that seems to be characteristic of all vertebrates. Yet its causes and purposes have not yet been completely identified. In addition to solely physiological causes, communicative purposes may play an important role, too. Within the context of the exhibition "Zzzz", large-format photographs of yawning humans and non-human primates are attached to window-panes at the MPI-EVA's Wolfgang Koehler Primate Research Center ("Pongoland") at the Zoo Leipzig. This exhibition is part of a larger exhibition called "buchstäblich" (engl. "literally") that takes place from March 21 to April 28, 2019.

African wild apes notice and often react to novel items in their environment

An international team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, analyzed video from remote camera-trap devices placed in ape-populated forests throughout Africa to see how wild apes would react to these unfamiliar objects. Responses varied by species, and even among individuals within the same species, but one thing was consistent throughout: the apes definitely noticed the cameras.

New research leads the way in validating a promising human brain model

The human brain is one of the most complex organs. Its complexity challenges our ability to study its structure and function. As a result, many brain-related diseases are not fully understood and adequate treatments are often lacking. Scientists from Max Planck Institute of Psychiatry (MPI) were able to model a developmental disorder called neuronal heterotopia which can lead to intellectual disability and epilepsy. They used a model of brain development called brain organoids where human cells organize themselves in the petri dish into brain-like structures. These brain organoids enabled the researchers to accurately recapitulate the disease in the lab. They discovered that the cells contained in the organoids, derived from individuals affected by the disease, had a different morphology and navigation system. In particular the scientists were able to find a full new set of molecular signatures that are unique in the diseased cells, giving them now potential ideas of how they can identify possible targets and strategies to develop therapy for patients. Barbara Treutlein from the MPI for Evolutionary Anthropology contributed to this study.

Chimpanzees are well known for their extraordinary diversity of behaviors, with some behaviors also exhibiting cultural variation. An international research team led by the Max Planck Institute for Evolutionary Anthropology and the German Centre for Integrative Biodiversity Research (iDiv) investigated whether chimpanzee behavioral diversity is reduced under high human impact. By comparing sets of chimpanzee behaviors across a large number of social groups exposed to different levels of human disturbance, the scientists found a reduction in behavioral diversity when human impact was high.

Increased dust loads result in decreased chewing efficiency in chimpanzees

Periodical dust loads on foods places dietary-physiological stress on the digestive system in chimpanzees. This is the conclusion reached by an international research team headed by scientists from the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) in Leipzig. Their study implicates that extrinsic abrasive particles carried by dust-laden winds affect tooth wear and evolutionary fitness.

Different cultures, different habits and different behavioral patterns – this applies not only to humans but also to chimpanzees, one of our two closest living relatives. A team of researchers from the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) in Leipzig, Germany, and The University of Warsaw in Poland now describes a new ‘behavioral realm’ of the Eastern chimpanzee (Pan troglodytes schweinfurthii) of the Bili-Uéré region in Northern DR Congo, based on the results of a 12-year study.

Isotope analyses performed on single amino acids in Neandertals’ collagen samples shed new light on their debated diet

A specific feature of modern humans seems to be their frequent fish consumption, which can be determined by nitrogen isotope analyses of bone or tooth collagen. An international research team, led by researchers from the Max Planck Institute for Evolutionary Anthropology, discovered two late Neandertals characterized by exceptionally high nitrogen isotope ratios, which would traditionally be interpreted as the signature of freshwater fish consumption. By studying the isotope ratios of single amino acids, they however demonstrated that instead of fish, the adult Neandertal had a diet relying on large herbivore mammals and that the other Neandertal was a breastfeeding baby whose mother was also a carnivore. According to isotope data, Neandertals seem to have had a very stable diet over time, including after the arrival of modern humans in Europe.

Orangutans make complex economic decisions about tool use depending on the current 'market' situation

Flexible tool use is closely associated to higher mental processes such as the ability to plan actions. Now a group of cognitive biologists and comparative psychologists from the University of Vienna, the University of St Andrews and the University of Veterinary Medicine Vienna that included Isabelle Laumer and Josep Call, has studied tool related decision-making in a non-human primate species – the orangutan. They found that the apes carefully weighed their options: eat an immediately available food reward or wait and use a tool to obtain a better reward instead? To do so the apes considered the details such as differences in quality between the two food rewards and the functionality of the available tools in order to obtain a high quality food reward, even when multidimensional task components had to be assessed simultaneously. The study was conducted in cooperation with the Max Planck Institute for Evolutionary Anthropology at the Zoo Leipzig in Germany.

Humans are considered to be superior tool users and uniquely able to teach skills to apprentices. However, a clear understanding of the differences between humans and other animal species has been limited by our difficulty to perform natural cross-species comparisons. A research team from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and from the University College London, UK, compared humans' and chimpanzees' learning to crack the same species of nuts as they forage for food in the African forest.

The language we speak affects the way we process, store and retrieve information

Memory plays a crucial role in our lives, and several studies have already investigated how we store and retrieve information under different conditions. Typically, stimuli presented at the beginning and at the end of a list are recalled better than stimuli from the middle. But are these findings universal and generalizable across languages and cultures? An international research team, led by Federica Amici from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, has recently investigated this question.

New studies reveal deep history of Denisovans and Neanderthals in southern Siberia

Denisova Cave is the only site in the world known to have been occupied by both Denisovans and Neanderthals at various times. Two new studies published in the journal Nature, now put a timeline on when the two groups of archaic humans (hominins) were present at the site and the environmental conditions they faced before going extinct. The studies identify the age of the earliest Denisovans and Neanderthals in Southern Siberia. One of the studies, was led by Dr Katerina Douka from the Max Planck Institute for the Science of Human History, while the other one was led by Zenobia Jacobs of the University of Wollongong in Australia.

Scientists can reconstruct the feeding behavior and habitats of extinct vertebrates

Plant phytolith and water content cause differing degrees of tooth enamel abrasion in vertebrates. This is the conclusion reached by an international research team headed by scientists from Johannes Gutenberg University Mainz (JGU). Featured online before print in the journal PNAS, their study has implications for how tooth wear in extinct animals is interpreted and how this information can be employed to reconstruct their dietary behavior and habitats. Ellen Schulz-Kornas of the Max Planck Institute for Evolutionary Anthropology in Leipzig contributed to this research.